Circuit breakers are commonly used to protect electrical equipment from overload and short circuit events. Large circuit breakers that carry thousands of amps of current are oftentimes installed into metal-enclosed switchgear assemblies. Switchgear assemblies have large electrical conductors called bus bars (or “buss bars”) that carry current from a power source, such as a power utility, through the circuit breakers, to loads that are protected by the circuit breaker. These large circuit breakers, which can weigh hundreds of pounds, are typically lifted into the switchgear and racked by mounting the circuit breakers into a drawout (or draw out) circuit breaker cradle. A manually controlled or remotely operated mechanism is inserted into the cradle to turn a crank that racks the circuit breaker into the switchgear and completes an electrical circuit which is protected by the breaker.
A known switchgear assembly typically comprises a cabinet of three sections: a cable section, a bus section and a breaker or equipment section. The breaker section houses a drawout circuit breaker cradle, which simplifies mounting and dismounting of a circuit breaker from field serviceable connections, allowing for ease of installation, removal, and maintenance. The drawout circuit breaker cradle includes a carriage assembly (or chassis) for receiving and supporting a circuit breaker and moving it into or out of the breaker section to make or break contact with the turnable joint mounts (TJMs) bolted at a first end to the bus bar terminals. The TJMs have a second end with a double prong U-shape profile facing towards the breaker. At the rear end of the breaker section/cradle may be a backmold (e.g., a backplane), which is a dielectric barrier between the breaker and bus sections with the double pronged U-shape profile of the TJMs protruding through. The breaker, which translates back and forth on the carriage, has “clusters” (e.g., spring-tensioned double-sided finger connectors) at the rear thereof, i.e. facing the backmold. All of these electrical/mechanical connections, however, reduce conduction efficiency, produce heat and thus, further reduce the current carrying capacity (e.g., ampacity), requiring larger conductors and more material expense.